Abstract

Aims. We report the discovery of WASP-38b, a long period transiting planet in an eccentric 6.871815 day orbit. The transit epoch is 2 455 335.92050 +/- 0.00074 (HJD) and the transit duration is 4.663 h.

Results. The planet has a mass of 2.69 +/- 0.06 M-Jup and a radius of 1.09 +/- 0.03 R-Jup giving a density,rho(p) = 2.1 +/- 0.1 rho(J). The high precision of the eccentricity e = 0.0314 +/- 0.0044 is due to the relative transit timing from the light curves and the RV shape. The planet equilibrium temperature is estimated at 1292 +/- 33 K. WASP-38b is the longest period planet found by SuperWASP-North and with a bright host star (V = 9.4 mag), is a good candidate for followup atmospheric studies.